The Probabilistic Stability Analysis of Saturated-Unsaturated MH and CL Soil Slope with Rainfall Infiltration

다국어 초록 (Multilingual Abstract)

It is well known that the slope failure in unsaturated soil is the decrease in the matric suction, when the rain water infiltrates.
However, the seepage mechanism and the stability of unsaturated soil slope have not been well established in geotechnicalengineering. In this study, the suction profile and reliability index of saturated-unsaturated slope is studied at different rainfallcondition with intensity in the range of saturated hydraulic conductivity of MH and CL soil. The finite element seepage model isuncoupled with slope stability model to calculate the reliability index at different time of long duration uniform rainfall. For CL soilslope, the reliability index is slightly changed during and after rain fall infiltration. For the MH soil slope the wetting front remainsunsaturated up to a certain time of rainfall infiltration. After this time, the infiltrated rainfall reaches the ground water table andelevates it. The reliability index of the soil slope is thus reduced.

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